CatPatch

This repository contains images and KiCad files for a CAT5e subsnake and DI system.

A brief build log for the DI and breakout cable can be found here.

Pinouts

The system, as labeled, is pin-compatible with RAT and ETS audio twisted pair products. The silkscreen and wiring can be adjusted to make it compatible with other standards.

| RJ45 Pin | T568B | RAT & ETS | Radial & Whirlwind | |:--------:|:---------------------------------------------------------:|:---------:|:------------------:| | 1 | WO | 2+ | 1+ | | 2 | O | 2- | 1- | | 3 | WG | 3+ | 2+ | | 4 | B | 1- | 3+ | | 5 | WB | 1+ | 3- | | 6 | G | 3- | 2- | | 7 | WBr | 4+ | 4+ | | 8 | Br | 4- | 4- |

Sources

RAT CAT Snake | Radial Catapult | Whirlwind Catdusa

Cable

Shielded cable is needed when using phantom powered, Clear-Com, and DMX devices over twisted pair. These devices require pin 1/ground to work. An EtherCON connector does not indicate that a cable is shielded.

Dynamic mics and passive DIs may work without the recommended shield.

DI

The DI PCB supports the Jensen JT-DB-EPC transformer found in DIs like the Radial JDI. A more affordable transformer can be substituted and can be found in the BOM.

The simplest configuration of the board requires a transformer and 6k81Ω resistor. A stereo summing circuit can be added with a few resistors. See the schematic and the classic RaneNote for more details.

A drill template can be found in the docs folder.

Labels can be printed on standard ID cards and can be attached with 3M Command Strip adhesive.

Frequency Response

I just want the boards, how do I get boards?

The boards used for this project are shared at OSHPARK and can be ordered there.

BOM

Breakout Panel

| Item | Manufacturer | Quantity | Price Each | |:-------------------------------------------|:-------------|:--------:|-----------:| | CH1/10 1U rackmount chassis | Redco | 1 | $66.95 | | NE8FDV-B Vertical EtherCON | Neutrik | 7 | $4.17 | | NC3MXX-BAG Male XLR | Neutrik | 28 | $2.96 | | SBR Rubber Push-In Grommet 1-3/16" ID | - | 1 | $11.80/10 | | Neutrik Black Screw for etherCon | Neutrik | 14 | $.21 | | Neutrik DBA-BL D blank | Neutrik | 1 | $.73 | | Flat Head Screws | - | 2 | $6.49/50 | | Steel Locknut with Lock Washer | - | 2 | $8.72/100 | | N8FDV breakout PCB | Custom | 7 | - |

DI Box

| Item | Manufacturer | Quantity | Price Each | |:--------------------------------------------------------|:------------------|:--------:|-----------:| | Steel Project Box Pre-Punched for 5 D Series XLRs | Pro Speaker Parts | 1 | $16.65 | | NE8FDV-B Vertical EtherCON | Neutrik | 1 | $4.17 | | NC3FD-L-1-BAG Panel mount D XLR | Neutirk | 2 | $3.22 | | NJ3FP6C-BAG Panel mount D TRS | Neutrik | 2 | $5.76 | | JT-DB-EPC Transformer | Jensen | 1 - 2 | $73.08 | | OR | | | | | Transformer for PROAV2 and PRODI | Radial | 1 - 2 | $36.00 | | Neutrik Black Screw for etherCon | Neutrik | 2 | $.21 | | Flat Head Screws | - | 8 | $6.49/50 | | Steel Locknut with Lock Washer | - | 8 | $8.72/100 | | Press-Fit Threaded Standoffs | - | 4 | $9.14/25 | | Button Head Hex Drive Screw | - | 4 | $11.00/100 | | N8FDV breakout PCB | Custom | 1 | - | | DI breakout PCB | Custom | 1 | - |

Project Images